B"You like numbers, don't you? Nastia has a lot of numbers and she wants to share them with you! Isn't it amazing? Let a_i be how many numbers i ( 1 <= i <= k ) you have. An n x n matrix is called beautiful if it contains all the numbers you have, and for each 2 x 2 submatrix of the original matrix is satisfied: Make a beautiful matrix of minimum size. The first line contains a single integer t ( 1 <= t <= 10 ,000 ) -- the number of test cases. The first line of each test case contains 2 integers m and k ( 1 <= m, k <= 10^5 ) -- how many numbers Nastia gave you and the length of the array a , respectively. The second line of each test case contains k integers a_1, a_2, ldots, a_{k} ( 0 <= a_i <= m , a_1 + a_2 + ldots + a_{k} = m ), where a_i is how many numbers i you have. It's guaranteed that the sum of m and k in one test doesn't exceed 2 cdot 10^5 . For each t test case print a single integer n -- the size of the beautiful matrix. In the next n lines print n integers b_{i, j} ( 0 <= b_{i, j} <= k ; if position is empty, print b_{i, j} = 0 ) -- the beautiful matrix b you made up. Note that 0 in this problem represents a blank, not a number. Examples of possible answers for the first test case: begin{array}{cc} 1 & 1 4 & 0 end{array} hspace{0,5cm} begin{array}{cc} 1 & 4 1 & 0 end{array} hspace{0,5cm} begin{array}{cc} 4 & 0 1 & 1 end{array} Examples of not beautiful matrices for the first test case: begin{array}{cc} 1 & 0 4 & 1 end{array} hspace{0,5cm} begin{array}{cc} 4 & 1 7 & 1 end{array} hspace{0,5cm} begin{array}{cc} 1 & 0 4 & 0 end{array} The example of the not beautiful matrix for the second test case: begin{array}{cc} 3 & 4 & 0 & 2 & 2 3 & 2 & 3 & 3 & 0 0 & 1 & 0 & 0 & 0 3 & 0 & "...